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(a) List the six
steps involved in the object-oriented design process. |
[6] |
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Identify the problem
and identify the real world objects. |
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Identify the methods
or activities that define the objects. |
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Identify and establish
object visibility. |
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Establish the
interfaces. |
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Establish the object
classes. |
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Implement or reiterate
the design. |
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one mark for
each step |
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[6
marks] |
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(b) A program is
required to determine the area and perimeter of a variety of geometric figures. Each
figure is encapsulated with its own attributes to create a distinct class. |
[7] |
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Describe the
attributes and methods for a circle class that is to be constructed first. You are
required to list only the attributes and methods, no C++ code is required.Provide
explanations if unsure. |
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Attributes
for the Circle class: |
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radius |
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area |
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perimeter (or
circumference) |
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Methods
for the circle class: |
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get_known_attributes
(reads in radius) |
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compute_area |
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compute_perimeter |
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display_attributes |
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Marking
scheme: |
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As above --- 7 marks |
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Area and Perimeter ,
with correct methods --- 5 or 6 marks |
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Correct intention but
incorrect methods ---3 or 4 marks |
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Some correct ideas ---
1 or 2 marks |
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[7
marks] |
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(c) The design of a
rectangle class follows along the same lines as the circle class. |
[7] |
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Define the rectangle
class in C++. |
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deduct one
mark for each error or omission, minimum zero. |
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[7
marks] |
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